Techniques for the partial pyrolysis of feedstocks, as well as complete pyrolysis and gasification are known. Furthermore, high-temperature and low-temperature pyrolysis processes are known, and it is known in the art that these different processes work best with different feedstocks and give different resultants. However, obtaining consistency in the pyrolysis products has long been a problem. Prior systems have attempted to pass a pyrolysis agent through a fluidized bed of solid; however, this requires a highly-granular and reactive fuel for pyrolysis, and, as such, is limited in its application. Other systems for pyrolysis pass a pyrolysis agent through a solid bed of fuel, which requires a non-caking fuel with high mechanical strength. Likewise, high and low-temperature pyrolysis processes are each better suited to pyrolizing different feedstocks, limiting the range of feedstocks that specific prior art pyrolysis systems may process. As such, there is a need in the art for pyrolysis systems that may accept a wide variety of fuels.
Furthermore, though both high-temperature and low-temperature pyrolysis processes produce combustible gases and materials, these resultant combustibles are often low grade, and they often contain harmful impurities, such as Mercury and Sulfur, that may contaminate the environment when these materials are combusted. As such, there remains a need in the art for controlled methods for purifying the resultant products and sequestering noxious materials both internal to and external to the pyrolysis process in order to prevent them from entering into the environment.
Furthermore, prior art systems do not provide efficient heat transfer to feedstocks, that exhibit multiple lobes in their specific heat signatures. Therefore, there remains a need in the art for a method of matching the heat transfer rate and dwell timing of the pyrolysis process to that of the particular feedstock-specific heat complex function to provide a greatly improved thermal efficiency of the pyrolysis system.
Furthermore, though the acceptable input organic or synthetic materials for pyrolysis have ranged widely in the past, there remains a need for pyrolysis systems that may process municipal solid waste (MSW), with all of its varying energy densities and impurities, and provide stable and consistent BTU/ft3 product gases, in order to eliminate landfills, waste organic and synthetic materials, and animal waste. There also remains a need for clean, efficient systems for the gasification of coal to globally reduce the dependence on oil drilled and pumped from the Earth's crust.
Furthermore, prior art pyrolysis systems and methods have been limited to “un-conditioned” resultant gas values of less than about 94% methane content and lack other typical requirements of natural gas companies for resultant gas injection directly into natural gas companies' distribution lines. There remains a need for pyrolysis systems and methods that may produce resultant gas of a quality acceptable for direct injection into natural gas companies' distribution gas lines with little or no gas conditioning.
Furthermore, alternative energy systems such as wind and solar are dependent upon the availability of their respective sources of energy, wind and sunlight. Although these and other inconsistent alternative energy systems rely on energy storage, such as batteries for solar and batteries, inertia, heat storage, and compression for wind, there is a need in the art for an additional means for these inconsistent alternative energy sources to store their energy for the optimum utilization and distribution to our U.S. energy needs.
Furthermore, prior art pyrolysis systems and methods have overall efficiency challenges as the pure pyrolysis technologies are endothermic with the need for burners or other means of heat transfer into the pyrolysis reactor. There is need in the art to provide the pyrolysis reactor heat with the gasification of by-products, for example.
Furthermore, prior art pyrolysis systems and methods all disadvantageously directly couple and utilize feedstock feed mechanisms inside of an outside of the pyrolysis chamber(s) such that pyrolysis reactors must be increased or decreased in mass flow rate to avoid plugging problems and the like. There is a need in the art to provide a high BTU/ft3 pyrolysis system that is not prone to plugging, either from feedstock flow or pyrolysis byproducts.
Furthermore, prior art pyrolysis systems and methods are not capable of producing very high BTU gas energy densities without separate chemical catalysis measures to produce the methane content desired. There is a need in the art to provide a pyrolysis system that has self-contained catalysis capabilities for methanization, providing a high yield of methane product gas and a means to keep the catalyst surface area clean/available, to transfer heat from the burner heated retort into the interior volume of the feedstock, and that is, in part, made of a catalyst material, thereby providing increased catalyst mingling with the feedstock.
Furthermore, prior art pyrolysis systems and methods are not energy efficient in the removal of tars, liquors, and other sticky and difficult condensable materials. There is a need in the art to provide a pyrolysis system that has energy efficient means of removing sticky and other condensates from the resultant organic gases.